A truck driver who says he was abused and punched by his boss after just seven days on the job has been awarded more than $6000 compensation for being unjustifiably sacked.

Darryl Paton took Auckland firm Lendich Construction to the Employment Relations Authority (ERA) after losing his job in November last year.

He told the ERA he was working on the platform of a concrete-crusher machine when the firm's owner, identified in the ruling only as Mr Lendich, joined him on the platform and began pushing him.

Paton said he retreated by climbing down the ladder of the machine. Lendich followed him and assaulted and abused him.

Lendich pushed him in the chest with both hands, hit his hard hat off his head and punched him on the right cheek while yelling at him "p... off and f... off the property", Paton said.

Paton left the worksite and raised concerns about what had happened with the operations manager, who told him to go home, Paton said.

Later that day the operations manager called Paton and confirmed he did not have a job because Lendich did not want him around.

In response, Lendich told the ERA Paton's dismissal was justified because he "was useless".

Lendich denied assaulting Paton, and said he shoved Paton in the chest for Paton's own safety to get him out of the way of an "expel shoot" on the concrete-crusher machine.

Lendich admitted he had knocked Paton's hard hat off his head, but said he did that only because he thought it was a company hat and he did not want Paton to leave the worksite with it.

In fact, the hat was Paton's.

Paton said he had left the hat on the ground because he felt he needed to make a hasty retreat in the face of Lendich's unexpected and unexplained anger.

Lendich agreed that he did not tell Paton why he had been told to leave and that Paton was never given any explanation for his dismissal.

ERA member Rachel Larmer said in her ruling that Lendich repeatedly told the authority in very strong terms that he was completely justified in all of the actions he had taken.

"Mr Lendich maintains his actions towards Mr Paton were necessary and appropriate because he [Mr Lendich] takes health and safety extremely seriously and he had to take immediate action because believed Mr Paton was doing his job in an unsafe manner.

"Mr Lendich says after viewing Mr Paton working on the concrete crusher he concluded Mr Paton was 'completely useless' and a danger to himself, which is why he wanted him gone immediately." Larmer ruled that Paton's dismissal was "fundamentally flawed in all respects".

"Mr Paton was not given any information. He had no idea why Mr Lendich was so angry and upset, why he was being pushed around by Mr Lendich, why his hard hat had been knocked off him or why he had been ordered to leave immediately.

"No allegations or concerns were ever put to Mr Paton to respond to. Mr Lendich never explained why he was so angry at Mr Paton. There was no disciplinary process. There was also no explanation ever given to Mr Paton regarding the reasons for his dismissal.

"I find that these are serious and fundamental breaches of the most basic procedural fairness requirements which resulted in substantial unfairness to Mr Paton."

She ordered Lendich Construction to pay Paton $2630 in lost wages and $4000 in distress compensation.